The proposed work is related to the thrombotic process as well as to various aspects of diagnosis, function, viability and treatment of the ischemic myocardium. Specifically the work is directed towards assessing the effects of anti-platelet agents upon the ischemic myocardium. The study is experimental and will be conducted in anesthetized animals (dogs) subjected to coronary occlusion for various lengths of time. It is expected that the results will enhance our understanding of the changes (time and biochemical) involved during myocardial ischemia and thus allow a more rational approach to the treatment of the ischemic myocardium.